A standoff is typically a threaded separator of defined length used to raise one assembly above another. In electronic devices, standoffs are frequently used to raise a printed circuit board above a surface of a chassis.
Electronics for space applications may require shielding from radiation in all directions (4-pi shielding). Mounting items such as circuit boards or cards to shielded chassis walls typically requires expensive specialized hardware, including standoffs and other fastening components made of radiation shielding materials.